Insulation stripping unit



Ax'il 21, 1959 Filed April 10 1956 E. T. STOCKER INSULATION STRIPPINGUNIT 2 Sheets-Sheet 1 I/vv5/v 7-051 5 7." 5 may Aprifi 21, 1959 I E. T.STOCKER INSULATION STRIPPING UNIT 2 Sheets-Sheet 2 Filed April 10, 1956United States Patent Ofiice 2,882,769 Patented Apr. 21, 1959 INSULATIONSTRIPPING UNIT Edward T. Stocker, Groveland, Mass., assignor to WesternElectric Company, Incorporated, New York, N .Y., a corporation of NewYork Application April 10, 1956, Serial No. 577,238

4 Claims. (Cl. 81-951) This invention relates to an insulation strippingdevice and particularly to such a device for progressively crushing andstripping insulation from a conductor.

In the manufacture of wire wound resistance elements, as disclosed inthe co-pending application Serial No. 578,917, filed April 18, 1956 byG. H. Harmon and A. E.

Rockwood, the resistance elements are overwound and I lation from thewire at a fast rate at the outset and then reduce the stripping speedwhen the resistance of the remaining wire approaches the prescribedvalue.

Accordingly, the main object of this invention is a twospeed insulationstripper particularly suited for use with an impedance calibrator.

In accordance with the general features of the invention, the deviceutilizes a pairof spring loaded insulation crushing rollers and includesa drive for the rollers which is controlled through a two-speed clutchwhich permits driving the rollers at either of two speeds.

These and other features of the invention will be more readilyunderstood from the following detailed description taken in conjunctionwith the accompanying drawing, in which:

Fig. 1 is a top view of the device, partly in section;

Fig. 2 is an isometric view of the crushing roller support mechanism;

Fig. 3 is a side elevational view of the device showing the drivinggears for the crushing rollers and the buffers as seen in the plane ofline 33 of Fig. 1, and

Fig. 4 is a simplified side elevation view, on a reduced scale, showingthe exhaust cover for the device.

Referring now to the drawing, in general the insulation stripping deviceincludes a pair of spring biased, opposed, insulation crushing rollers 5and 6 that strip the insulation from a conductor such as 7 (which may beresistance wire being payed off of an overwound fiat type resistorelement 8); a buffer wheel 9 and 10 for continually polishing thecrushing surfaces of the rollers 5 and 6, respectively; a wire clipper11; a coaxial clutch 12 for controlling the speed of the rollers 5 and6; a drive motor 14; an air cylinder 15 for controlling the coaxialclutch 12; and an exhaust cover 13 through which stripped insulation maybe removed.

The upper roller 5 on the end of shaft 16 is mounted in the bifurcatedhousing 17 for limited movement about a pivot pin 18, as controlled bythe tensioning of spring 19 on the bolt 20 which threads into the lowerhousing 22 in which the lower roller 6 is mounted on the end of a shaft23. The housing 17 will be pivoted slightly upward or clockwise when awire is passed between rollers and the tensioning of spring 19 therebyapplies a crushing pressure therebetween. The amount of displacement ofthe housing 17 by the wire is not sufiicient to break the mesh betweengears 25 and 26 which are the power take-off gears for driving the upperroller from the shaft 23. The shaft 23 in turn is driven by the outputshaft 38 of the clutch 12. The buffers 9 and 10 are driven by gears 29and 30 on shafts 16 and 23, through the idler gears 27 and 28 and gears21 and 24 on shafts 37 and 43 to which the buffer wheels 9 and 10,'respectively, are mounted. These buffers keep the surfaces of therollers clean, thereby preventing jamming between rollers and insuringgood electrical contact between the Wire being stripped and the rollerswhich are grounded. In Fig. 1 only portions of the shafts 16 and 37 forroller 5 and bufier 9, respectively, are shown, the gears 21, 27, 25 and29 having been omitted to permit disclosing shaft 23 (which is driven bythe output shaft 38 of the clutch) as well as the gears 26 and 30 on theshaft 23. The vertical disposition of the gearing and shafts for therollers and buffers is complete in Fig. 3. From this it is seen thatgear 26 on the shaft 23 to which roller 6 is attached, is meshed withand drives the gear 25 and its shaft 16 for roller 5.

A 1,725 r.p.m. motor 14 drives a jack shaft 32 at 57.5 r.p.m. through aworm gearing 31 having a gear reduction of 30 to l. The jack shaft inturn drives a fast drive clutch member 33 and a slow drive clutch member34 at about 172.5 rpm. and 19.2 r.p.m through a 3 to 1 step-up andreduction arrangement 35 and 36, respectively.

Output shaft 38 of the clutch extends through and is coaxial with andfree to slide longitudinally and rotate within the slow drive shaft 39which is pinned to clutch member 34. A selector member 41 havingclutching,

faces 67 and-68 for engaging faces 69 and 70 of fast and slow speedclutch members 33 and 34, respectively, is pinned to the output shaft 38and will rotate at the speed of the clutch face with which it is meshed.The faces of the plates 33, 34 and 41 are notched to provide for apositive gripping therebetween. The fast or slow speed selection isaccomplished by axial movement of the output shaft 38 within the slowdrive shaft 39, by means of a double-acting air cylinder 15 whose outputpiston 42 butts with one end of an extension shaft 44 which extendsaxially from output shaft 38 and is coaxial within the fast drive shaft40. When the piston is advanced the selector 41 meshes with the low orthe slow speed clutch member 34 and when retracted, a spring 45, mountedagainst a thrust bearing 46, disengages the selector from the slow driveclutch face and meshes it with the fast drive clutch face of member 33.This air cylinder 15 is of conventional design and may be controlled bysolenoids to advance or retract its piston.

This control may be manual or automatic, such as is disclosed in theaforementioned co-pending application. The other end of the output shaft38 has a slot 47 for receiving a corresponding tongue 48 at the end ofshaft 23 for driving the rollers and buffer wheels. This tongue andgroove arrangement permits axial movement between the output shaft 38and the shaft 23 required for operation of the coaxial clutch.

A clipper 11 is provided for clipping the wire in response to a signal(or other manual control) of an electromagnetic device 51 which operatesto turn the shaft 52 in housing 22 to which the clipper plate 63 isattached. The clipper plate 63 cooperates with the fixed plate 64 whichis provided with an opening 65 through which the Wire normally passes.This clipper and plate 64 may be mounted by means of insulating bushingsto the housings 22 to electrically isolate the clipper as may berequired, for example, in calibrating bare wire resistors. When used inconjunction with the calibrator of the aforementioned application, thesolenoid 51 receives its electrical signal from the: calibrator.

An exhaust system J's-provided forcontinuously removing crushedinsulationand-wire (which is clipped from-v dashed lines in Fig, 4 sincethey are on the inner surface,

of the cover) may be provided for contactingthe rollers.

It is to be understood that the above described arrangements are simplyillustrative of the application of the principles .of the invention.Numerous other arrangements may be readily devised by those skilledinthe art which will embody the principles of the inventionand fallwithin'the spirit and scope thereof.

What is claimed is:

1. In an insulation stripping device having a pair of opposing"insulation crushing rollers,.'means for driving said rollerscomprising adriver, an output shaft for driving the rollers, a first and. asecondinput shaft, means controlled by the driver for rotating the inputshafts at different speeds, a member on each of-the. input shafts havingopposingclutching faces, a member on the output shaft having clutchingfaces on opposed sides thereof and interposed between -the:clutchingfaces of the memberslon the input shafts, and means for selectivelyengaging the clutching: faces ofv the output shaft member and theclutching faces of the input shaft members.

2. loan-insulation strippingdevice' having a. pair of opposinginsulation crushing rollers and adrive' shaft therefor, means for:driving said rollers comprising a driver, an output shaft for drivingthe drive shaft, coupling'meansbetvveen the output shaft and the driveshaft topermit axial movement therebetween, a first and a second inputshaft, means controlled by the driver for driving the input shafts atdifferent speeds, at least one of the input shafts being positionedcoaxiallywith the output shaft, a pair of opposing members. on the inputshafts with, opposing-clutching faces, a; member, on the outputThis-comprises an exhaust cover 13 which.

shaft having clutching faces on opposed sides thereof and interposedbetween the clutching faces of the input shafts, and means for movingthe output shaft axially to selectively move one of the clutching facesof the output shaft member into engagement with the clutching faces ofthe input shaft members.

3. In a device having a drivable member, means for driving the membercomprising a driver, an output shaft for driving the member, a first andsecond input shaft, meanslcontrolled by the driver for rotating thevinput shafts at different speeds, a member on each of the input shaftshaving opposing clutching faces, a memberonthe output shaft havingclutching faces on opposite sides thereof and interposed between theclutching faces of the members on the input shafts, and means forselectively engaging the clutching faces of the output shaft member andthe clutching faces of the input shaft members.

4. In a device having drivable companion members,

means fordriving themembers comprising a driver, an

output shaft'for driving'themembers, afirst and a second input shaftwith at least one-shaft having an axial passage' extending therethroughfor mounting, the shaft coaxially with the output shaft, meanscontrolled by the driver for rotating the input shafts atdilferent'speeds, a

member oneach of the input" shafts having opposing clutching faces, amember on the output shaft having clutchingfaces on opposite sidesthereof and interposed between the clutching faces of the members on theinput shafts,- and means for' selectively axially" displacing theoutput'shaft to engage the clutching faces of the output shaft memberand the clutchingzfaces of the input shaft members;

References Cited in the file of this patent UNITED STATES PATENTS239,650, Coats: Apr. 5, 1881 447,462 Crane M r- 3, 1891 761,905 PotterJune 7, 1904 878,493 Barnes Feb. 11, 1908 1,706,675 Osgood Mar. 26, 19291,930,219 Zimber Oct. 10; 1933: 2,220,541 Peterson Nov. 5,.19402,225,200 Amesz- Dec. 17,1940.

